"I saw Aguero in the tunnel, no broken nose, no broken head, his face as nice as always. If he doesn't go to the floor, it's not a red card," said the Portuguese.
Mourinho defended his team's approach in Thursday's 0-0 derby draw with Manchester City, hailing their spirit as they held on with 10 men.
United had only 31 per cent possession and created few chances as they battled for a share of the spoils that left them a point behind fourth-placed City in the Premier League.
But Mourinho, who also questioned Sergio Aguero's reaction in the incident which saw United midfielder Marouane Fellaini sent off in the 84th minute, was in no mood for apology.
"They had more ball, they had more chances but I have to defend the players and the spirit of my players and say they were amazing the way they fight," he said, after his team extended their unbeaten run to 24 games.
United could have grabbed the lead just before halftime when midfielder Ander Herrera missed a glorious chance, heading wide from close range when left unmarked, and Mourinho felt they would have deserved the advantage.
"In the first half we controlled easily the game, we controlled easily the defensive side of the game and we were always dangerous on the counter-attack and we had two good chances to score," he said.
"Marcus [Rashford] gave their defenders lots of problems, they stopped him sometimes with lots of fouls, so for me the spirit was amazing and the first half was really good.
"In the second half, I think they were stronger than us. Despite the fact that we were very strong defensively, we didn’t create enough problems in attack and we allowed them to be more offensive and play more in our half," he added.
Read the full article on eurosport.co.uk: Mourinho digs at 'smart' Aguero after United's Fellaini sees red